JPH07290257A - Laser marking method - Google Patents

Abstract

PURPOSE:To maintain a specified laser power, to draw a stable marking line and to eliminate the damage of an object by operating a galvanometer from just before the start point of drawing of the marking line to the point beyond the end point of drawing. CONSTITUTION:A marking condition input section 11 displays set marking information on a display device 2 and edits the marking information in accordance with the information from an input device 3. A marking data forming section 12 forms marking data for moving a galvanometer, etc., in accordance with such information. An extension data forming section 13 adds the necessary extension data to the data in accordance with the data described above. The data are interpreted in a marking control section 14, which outputs a control signal for marking to a Q switch driver 4 and a galvanometer driver 5. This Q switch driver 4 executes on/off control of a laser by outputting an RF signal to a Q switch 61 in a laser oscillator 6 when the driver receives a control pulse signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser marking method in a one-stroke type laser marking device for marking a character or a pattern by two-dimensionally scanning a laser beam by two galvanometers having a relatively large response delay. , Especially the dots that form the marking lines created by laser irradiation at the start and end of marking,
That is, the present invention relates to a method for controlling an interval between laser pulse dots and a deformation prevention control method for a marking figure.

[0002]

2. Description of the Related Art Conventionally, a marking object is damaged due to an initial laser pulse which is repeatedly irradiated at a marking start point due to a response delay in the galvanometer, a deceleration of the galvanometer near the marking end point, and a galvanometer. There was a laser marking device that prevents the shortage of laser pulse irradiation caused by the response delay of.

For example, Japanese Laid-Open Patent Publication No. 2-299786 discloses a laser marking apparatus using two galvanometers, in which a laser pulse is irradiated at a high density at a marking start point due to a response delay in the galvanometer, and a marking object is In order to prevent damage,
A method is disclosed in which an operation command signal is output to a galvanometer at a marking start point, and then a laser pulse is controlled not to be output until the galvanometer actually operates.

Further, Japanese Laid-Open Patent Publication No. 2-211989 discloses a laser marking device using two galvanometers, in which a laser beam is generated near a marking start point and a marking end point due to a response delay of the galvanometer and acceleration / deceleration of the galvanometer. A method of changing the output interval of laser pulses based on the operation of a galvanometer is disclosed for the purpose of preventing high-density irradiation of pulses.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the marking method disclosed in Japanese Patent No. 786, due to the acceleration / deceleration control and response delay of the galvanometer at the start of galvanometer operation, the laser pulse dot interval forming the marking line at the beginning and end of drawing is not constant, There is a problem that a portion overlapping the laser pulse dot is formed and the marking object is damaged.

Furthermore, at the end of galvanometer operation,
Due to the difference in response time between the galvanometer and the laser oscillation, near the end of drawing the marking line, the laser oscillation ends before the end of the galvanometer operation, the laser pulse dot runs short, and the marking line There was also the problem that it would be shorter than expected.

Further, in the marking method disclosed in Japanese Patent Laid-Open No. 211989/1990, when the laser is oscillated at a high frequency, the laser power is not constant near the marking start point and the marking end point. There was a point.

Further, in the method disclosed in Japanese Patent Laid-Open No. 2-299786 and Japanese Patent Laid-Open No. 211989/1990, when marking an oblique line or an arc line with respect to the axes of two orthogonal galvanometers, the two axes There is also a problem that the marked diagonal line or arc line is deformed because the galvanometers have different operating speeds and the response times of the galvanometers are different.

[0009]

In order to solve the above problems, the laser marking method of the present invention is a laser marking method in which a laser beam is scanned by using a galvanometer to perform marking, from the starting point of drawing a marking line. Also, the operation of the galvanometer is started from this side, and the galvanometer is controlled to operate even when the drawing line drawing end point is exceeded.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of this embodiment. The main controller 1 includes a marking condition input unit 11, a marking data generation unit 12, an extension data generation unit 13, a marking control unit 14, and a line end pulse. A control unit 15 is provided, a display device 2 such as a CRT or a liquid crystal display, and an input device 3 such as a keyboard are connected, and the marking data is edited based on the information input from the input device 3. A marking control signal is output based on this marking data.

The marking condition input unit 11 displays preset marking information on the display device 2 and edits the marking information based on the information input from the input device 3.

The marking data generation unit 12 does not output data for drawing a straight line for drawing a pattern or character designated by the marking information edited by the marking condition input unit 11, data for drawing an arc line and laser. Marking data such as data for moving the galvanometer to an arbitrary position is generated.

Based on the marking data generated by the marking data generating unit 12, the extension data generating unit 13 converts the data of the portion where the marking line is interrupted and the data of the portion where the scanning direction of the marking is different by an arbitrary angle or more. Add extension data.

The marking control section 14 decodes the marking data created by the extension data generating section 13 and outputs a control signal for marking to the Q switch driver 4 and the galvanometer driver 5 based on the marking data. To do. Further, the line-end pulse control section 15 provided in the marking control section 14 deletes a predetermined amount of pulses at the beginning and end of drawing the marking.

When the Q switch driver 4 receives the control pulse signal output from the marking control unit 14, the Q switch driver 6 is installed in the laser oscillator 6.
An RF (Radio Frequency) signal is output to 1 to control ON / OFF of the laser. Further, the Q switch fast pulse suppressor 41 provided in the Q switch driver 4 adjusts the power of the RF signal so as to suppress the laser pulse output having a high peak value output at the start of laser oscillation.

The laser power source 7 is the laser oscillator 6
Power supply to the laser oscillator 6
Cool the condenser inside. Here, when the Q switch element 61 receives the RF signal output from the Q switch driver 4 via the Q switch fast pulse suppressor 41 at the start of laser oscillation, it outputs a steeple at the start of laser oscillation. The power of the RF signal is controlled so as to suppress the laser pulse output having a high value.

Upon receiving the control signal output from the marking controller 14, the galvanometer driver 5 drives and controls a galvanometer (not shown) installed in the scanning optical system 8.

The scanning optical system 8 has the galvanometer, a reflection mirror, an fθ lens, etc., and scans the incident laser light by driving the galvanometer.

A workpiece is placed on the work 9 and is irradiated with laser light scanned by the scanning optical system 8.

Next, the operation of this embodiment will be described with reference to FIG.

When the main controller 1 is activated, first, the marking condition input unit 11 is activated, and the marking condition input unit 11 displays preset marking information on the display device 2 and also the input device 3 The marking information is edited on the basis of the information input from.

Next, the marking data generating unit 12 is activated, and the marking data generating unit 12 draws a straight line for drawing a design or a character designated by the marking information edited in the marking condition input unit 11. , Marking data such as data for drawing an arc or data for moving a galvanometer to an arbitrary position without outputting laser light is generated.

Next, the extension data generation unit 13 is activated, and the extension data generation unit 13 connects the marking data created by the marking data generation unit 12 with the data at the portion where the marking line is interrupted and the marking line. However, extension data is added to the data of the portion where the scanning direction of the galvanometer during marking changes by a predetermined angle or more. That is, as shown in FIG.
The data for the extended portion Z is added to the data for the portion Y and the portion Y for which the scanning direction changes by a predetermined angle or more.

Next, the marking control unit 14 is activated, and in the marking control unit 14, the extension data generation unit 1
The marking data to which the extension data is added is decoded in 3 and the line end pulse control section 15 deletes a predetermined amount of laser pulse control signal at the marking start and end portions of the marking, and then the Q switch driver 4 and Marking control signal (laser pulse control signal and galvanometer control signal) to the galvanometer driver 5
Is output.

Next, when the Q switch driver 4 receives the laser pulse control signal output from the marking control unit 14, the Q switch fast pulse suppressor 41 outputs a high peak value at the start of laser oscillation. The power of the RF signal is adjusted so that the laser pulse is suppressed, and the power-adjusted RF signal is output to the Q switch element 61.

Next, the laser oscillator 6 outputs laser light whose output is controlled based on the RF signal output from the Q switch driver 4 and the power supplied from the laser power supply 7.

Next, the laser light output from the laser oscillator 6 is incident on the scanning optical system 8. Here, the galvanometer constituting the scanning optical system 8 is drive-controlled based on the galvanometer control signal output from the marking controller 14 by the galvanometer driver 5, and the laser beam is driven by driving the galvanometer. The work 9 is scanned.

Next, the operation at the time of adding extension data in the extension data generator will be described with reference to FIG.

First, when the control signal output from the Q switch fast pulse suppressor 41 suppresses the laser pulse output having a high steeple value output at the start of laser oscillation, the laser pulse control signal is output from the marking control unit 14. From the time when the laser pulse is output to the time when the output of the laser pulse actually reaches the markable output power (first pulse suppressor operation time). Here, the operation time of the first pulse suppressor changes depending on the oscillation frequency of the laser and the like.

At the beginning of drawing the marking line, the response delay from the output of the control signal from the marking control unit 14 to the operation of the galvanometer and the acceleration from the start of the operation of the galvanometer to the target operation speed are reached. Time, that is, the time from the output of the control signal from the marking control unit 14 to the galvanometer driver 5 until the galvanometer reaches the target operating speed (galvanometer acceleration time) occurs, and the marking line is drawn. Similarly for the end, the time from the reception of the control signal from the marking control unit 14 to the actual stop of the galvanometer driver 5 operating at the target operation speed (galvanometer deceleration time).
Occurs. Here, the galvanometer acceleration time and the galvanometer deceleration time change depending on the target operating speed of the galvanometer and the like.

Here, when the fast pulse suppressor operating time is longer than the galvanometer acceleration time at the beginning of drawing the marking line, only the galvanometer scanning time corresponding to the fast pulse suppressor operating time, When the marking data for drawing a marking line in the same scanning direction as the galvanometer scanning direction at the start of marking is added to the original marking data, and the galvanometer acceleration time is longer than the first pulse suppressor operation time. For the galvanometer scanning time corresponding to the galvanometer acceleration time, the marking data for drawing the marking line in the same scanning direction as the galvanometer scanning direction at the start of marking is added to the original marking data.

At the end of drawing the marking line, the marking data for drawing the marking line in the same scanning direction as the galvanometer scanning direction at the end of marking is the original marking for the galvanometer scanning time corresponding to the galvanometer deceleration time. Appended to the data.

Next, the relationship between the operation of the galvanometer and the laser oscillation with respect to the control signal output from the marking controller will be described with reference to FIGS. 2 and 3.

FIG. 2 is a diagram showing the relationship between the control signal and the operation when the fast pulse suppressor operation time is longer than the galvanometer acceleration time.

In FIG. 2, T1 is the galvanometer acceleration time, T2 is the fast pulse suppressor operation time,
T3 indicates a galvanometer deceleration time.

First, at the beginning of drawing the marking line,
Since T1 <T2, data corresponding to the fast pulse suppressor operation time T2 is added to the original marking data.

As a result, the galvano control signal and the laser pulse control signal output from the marking control unit 14 are output earlier by the fast pulse suppressor operating time T2 than when the original marking line is drawn.

Next, the galvanometer is activated in accordance with the galvanometer control signal output earlier, and reaches the target operating speed after the galvanometer acceleration time T1 has elapsed.

Further, the laser oscillation reaches the laser output capable of marking after the fast pulse suppressor operation time T2 has elapsed after the laser pulse control signal output earlier was output.

At the end of drawing the marking line, data corresponding to the galvanometer deceleration time T3 is added to the original marking data.

As a result, the galvano control signal output from the marking control unit 14 is delayed by a time corresponding to the galvanometer deceleration time T3 as compared with the case of the original marking data. However,
The laser pulse control signal output from the marking control unit 14 is output by the line end pulse control unit 15 in this range so that laser oscillation is not performed in the range corresponding to the galvanometer deceleration time T3. The laser pulse control signal to be deleted is deleted.

Next, the galvanometer gradually decelerates from the target operating speed and finally stops by the galvanometer control signal of the portion corresponding to the galvanometer deceleration time T3.

Further, in the laser oscillation, since the laser pulse control signal is not output corresponding to the additional data, the laser oscillation is ended at the same timing as the original marking data.

FIG. 3 is a diagram showing the relationship between the control signal and the operation when the fast pulse suppressor operation time is shorter than the galvanometer acceleration time, and in FIG.
T2 and T3 indicate the same time as in the case of FIG. 2 described above.

First, at the beginning of drawing the marking line,
Since T1> T2, data corresponding to the galvanometer acceleration time T1 is added to the original marking data.

As a result, the galvano control signal output from the marking control unit 14 is output earlier by the galvanometer acceleration time T1 than when the original marking line is drawn. However, regarding the laser pulse control signal, the laser pulse control signal to be output during the period is deleted by the line end pulse control unit 15 so that the laser oscillation is not performed for a time corresponding to T1-T2.
Actually, the first pulse suppressor operation time T2 is output earlier than the original marking data.

Next, the galvanometer is activated in accordance with the galvanometer control signal output earlier, and reaches the target operating speed after the galvanometer acceleration time T1 has elapsed.

The laser oscillation reaches the markable laser output after the fast pulse suppressor operation time T2 has elapsed after the laser pulse control signal output earlier was output.

At the end of drawing the marking line, data corresponding to the galvanometer deceleration time T3 is added to the original marking data.

As a result, the galvano control signal output from the marking control unit 14 is delayed by a time corresponding to the galvanometer deceleration time T3 as compared with the case of the original marking data. However,
The laser pulse control signal output from the marking control unit 14 is output by the line end pulse control unit 15 in this range so that laser oscillation is not performed in the range corresponding to the galvanometer deceleration time T3. The laser pulse control signal to be deleted is deleted.

Next, the galvanometer gradually decelerates from the target operating speed and finally stops by the galvanometer control signal of the portion corresponding to the galvanometer deceleration time T3.

Further, in the laser oscillation, since the laser pulse control signal of the portion corresponding to the additional data is not output,
The laser oscillation is ended at the same timing as the original marking data.

[0054]

As described above, according to the laser marking method of the present invention, a laser that forms a marking line near the start and end of drawing on the marking line regardless of the acceleration / deceleration control of the galvanometer and the response delay. The pulse dot interval can always be kept constant,
Since the laser pulse dot interval is not changed, the laser power is always constant even when the laser is oscillated at a high frequency, and a more stable marking line can be drawn, damaging the marking object. It won't let you.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is a timing chart showing the operation of the embodiment of the present invention.

FIG. 3 is a timing chart showing the operation of the embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between extension data and marking lines according to an embodiment of the present invention.

[Explanation of symbols]

 1 Main Controller 11 Marking Condition Input Unit 12 Marking Data Generation Unit 13 Extension Data Generation Unit 14 Marking Control Unit 15 Line End Pulse Control Unit 2 Display Device 3 Input Device 4 Q Switch Driver 41 Q Switch Fast Pulse Suppressor 5 Galvanometer Driver 6 Laser Oscillator 61 Q-switch element 7 Laser power supply 8 Scanning optical system 9 Work

Claims (5)

[Claims] 1. A laser marking method for marking by scanning a laser beam with a galvanometer, wherein the galvanometer operation is started before the marking line drawing start point, and the marking line drawing end point is exceeded. Also, a laser marking method is characterized in that the galvanometer is controlled so as to operate. 2. The laser marking method according to claim 1, wherein the laser pulse control signal to be output while the galvanometer operates beyond the end point of drawing the marking line is deleted. 3. A galvanometer acceleration time from when the galvanometer receives a start signal to when it reaches a target operating speed, and a laser output capable of marking after the laser oscillator receives a pulse control signal at the start of laser oscillation. The first data generated on the basis of the first pulse suppressor operation time up to the start time of the galvanometer is started before the drawing start point of the marking line, and the galvanometer is operating at a predetermined operation speed. Even if the galvanometer crosses the end point of drawing the marking line by the second data generated based on the galvanometer deceleration time from when the galvanometer receives the operation end signal to when the galvanometer actually stops. A laser marking method comprising: 4. The galvanometer acceleration time is the sum of the response delay time of the galvanometer and the time in the acceleration range from the start of operation of the galvanometer until the target operating speed is reached, and the galvanometer 4. The laser according to claim 3, wherein the deceleration time is a time obtained by combining a response delay time of the galvanometer and a time in a deceleration region until the galvanometer decelerates from a target operating speed and stops. Marking method. 5. The galvanometer acceleration time is longer than the fast pulse suppressor operating time,
After the activation signal for the galvanometer is output, the galvanometer acceleration time and first pulse
4. The laser marking method according to claim 3, wherein the laser pulse control signal is not output until a time difference from the suppressor operation time has elapsed.